Your tradeskill must be at least level 93 (which is when you receive the mail to start this quest).
Acquire 1 Effulgent Coal before you head to the Stonebrunt Highlands or visit the merchant (Sata - Faction Merchant) in the tent to the left of him and purchase your fuel.
Use the Ulteran Spires near each location for quick porting between locations for every step that requires travel between zones.
Though it is not a quest reward, the Mara Spirit Anchor that appears in Cardin Ward in the second to last step will remain in that location, making travel to and from Mara and Obol Plains for crafting, harvesting, and adventure easy.
Steps
Speak to Keevan Fastmarch at ( -125, 13, 178 ) Copy/waypoint -125, 13, 178 in the Hidden Camp in Feerrott
Speak to Ghostclaw at ( 129, -7, -87 ) Copy/waypoint 129, -7, -87 on the beach in Feerrott.
Speak to Researcher Tahar at ( -200, 366, 588 ) Copy/waypoint -200, 366, 588 in Quel'ule in the Stonebrunt Highlands. If you are using fast travel, then you will want to choose the location closest to the center of the of the map.
Examine the Bundle of Ulteran Spire Technology he gives
Scribe recipe for Spire Device and craft at Work Bench
There is a Work Bench at ( -133, 366, 615 ) Copy/waypoint -133, 366, 615.
Ghostclaw will give you Armlet of Ethernere, which gives the user a superficial appearance of belonging in the Ethernere. It is not required that you use the illusion to continue the quest. The Armlet also has some good crafting stats, so you'll want to hang onto it.
Use the crafted device on a departing spirit in the Somborn Cemetary in Loping Plains (near ( -429, 16, 70 ) Copy/waypoint -429, 16, 70).
Make sure you don't have ranged auto selected or wand or you will kill the spirit.
Tether the spirit anchor at the Ethernere Crystal just outside Cardin Ward, by clicking the glowing green spot on the ground ( -516, 0, -62 ) Copy/waypoint -516, 0, -62.
Return to Captain Ethan in the Village of Shin using the Isle of Mara Reality Anchor in the room with the fuel merchant in Obol Plains at ( -410, 15, 56 ) Copy/waypoint -410, 15, 56.